Shingling conveyors are used to stack finished envelopes from an inserter or wrapper. They are the most common mechanism to collect finished envelopes produced by an inserter in today's mailing environment. With this type of conveyor, an operator will “sweep the belt”, which essentially amounts to an operator using both his/her hands to pull as many envelopes/mailpieces together as possible, and still be able to lift them into an awaiting mail tray which is typically on a table or cart near the end of the conveyor. Because the mailpieces are manually lifted off the conveyor and carried to the tray, the size of the bundle of mailpieces is limited by the strength and dexterity of the operator. Failure of the operator to grip the selected bundle of mailpieces firmly enough can easily result in loosing control of the center of the bundle when lifting and moving the bundle to a mail tray which is positioned to the side or behind the operator. It should be readily apparent that tumbling a bundle of mailpieces to the floor during the sweeping operation causes a significant delay in operations due to clean up.
The sweeping process is repeated until the tray is full. Tray break marks or an offset of a single mailpiece alerts the operator where the end of the bundle of mailpieces occurs and a new tray must be started. This process is time consuming, risks missing a tray break and requires a significant amount of lifting. In addition, significant time can be saved by eliminating the step where an operator has to search for the tray break mark. If the operator fails to sweep the stacker conveyor at the speed at which the inserter produces mailpieces, the inserter must be stopped until there is free space on the stacker conveyor. Stoppage effects production throughput. Operator fatigue from lifting, turning and placing a mail bundle in the correct mail tray increases the probability of tray sweeping errors, of stoppage for operator rest or additional staff to allow for rest without inserter stoppage.
Hence a need exists for an on-edge conveyor where common components have been ergonomically positioned to permit the filling of a mail tray in a matter of seconds (e.g. less than 5 seconds) with minimal lifting of weight, i.e. a quantity of envelopes that has already been offset can be pulled over the rolled/rounded edge of the conveyor into an awaiting mail tray supported on a roller conveyor. The operator would then push the full tray to the side, load another empty tray, and repeat the process.